// https://syzkaller.appspot.com/bug?id=16a7f16e9182bbfdbd2142306a82a41d4debb670
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

#include <linux/loop.h>

static unsigned long long procid;

struct fs_image_segment {
  void* data;
  uintptr_t size;
  uintptr_t offset;
};

#define IMAGE_MAX_SEGMENTS 4096
#define IMAGE_MAX_SIZE (129 << 20)

#define sys_memfd_create 319

static unsigned long fs_image_segment_check(unsigned long size,
                                            unsigned long nsegs,
                                            struct fs_image_segment* segs)
{
  if (nsegs > IMAGE_MAX_SEGMENTS)
    nsegs = IMAGE_MAX_SEGMENTS;
  for (size_t i = 0; i < nsegs; i++) {
    if (segs[i].size > IMAGE_MAX_SIZE)
      segs[i].size = IMAGE_MAX_SIZE;
    segs[i].offset %= IMAGE_MAX_SIZE;
    if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size)
      segs[i].offset = IMAGE_MAX_SIZE - segs[i].size;
    if (size < segs[i].offset + segs[i].offset)
      size = segs[i].offset + segs[i].offset;
  }
  if (size > IMAGE_MAX_SIZE)
    size = IMAGE_MAX_SIZE;
  return size;
}
static int setup_loop_device(long unsigned size, long unsigned nsegs,
                             struct fs_image_segment* segs,
                             const char* loopname, int* memfd_p, int* loopfd_p)
{
  int err = 0, loopfd = -1;
  size = fs_image_segment_check(size, nsegs, segs);
  int memfd = syscall(sys_memfd_create, "syzkaller", 0);
  if (memfd == -1) {
    err = errno;
    goto error;
  }
  if (ftruncate(memfd, size)) {
    err = errno;
    goto error_close_memfd;
  }
  for (size_t i = 0; i < nsegs; i++) {
    if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) {
    }
  }
  loopfd = open(loopname, O_RDWR);
  if (loopfd == -1) {
    err = errno;
    goto error_close_memfd;
  }
  if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
    if (errno != EBUSY) {
      err = errno;
      goto error_close_loop;
    }
    ioctl(loopfd, LOOP_CLR_FD, 0);
    usleep(1000);
    if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
      err = errno;
      goto error_close_loop;
    }
  }
  *memfd_p = memfd;
  *loopfd_p = loopfd;
  return 0;

error_close_loop:
  close(loopfd);
error_close_memfd:
  close(memfd);
error:
  errno = err;
  return -1;
}

static long syz_mount_image(volatile long fsarg, volatile long dir,
                            volatile unsigned long size,
                            volatile unsigned long nsegs,
                            volatile long segments, volatile long flags,
                            volatile long optsarg)
{
  struct fs_image_segment* segs = (struct fs_image_segment*)segments;
  int res = -1, err = 0, loopfd = -1, memfd = -1, need_loop_device = !!segs;
  char* mount_opts = (char*)optsarg;
  char* target = (char*)dir;
  char* fs = (char*)fsarg;
  char* source = NULL;
  char loopname[64];
  if (need_loop_device) {
    memset(loopname, 0, sizeof(loopname));
    snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid);
    if (setup_loop_device(size, nsegs, segs, loopname, &memfd, &loopfd) == -1)
      return -1;
    source = loopname;
  }
  mkdir(target, 0777);
  char opts[256];
  memset(opts, 0, sizeof(opts));
  if (strlen(mount_opts) > (sizeof(opts) - 32)) {
  }
  strncpy(opts, mount_opts, sizeof(opts) - 32);
  if (strcmp(fs, "iso9660") == 0) {
    flags |= MS_RDONLY;
  } else if (strncmp(fs, "ext", 3) == 0) {
    if (strstr(opts, "errors=panic") || strstr(opts, "errors=remount-ro") == 0)
      strcat(opts, ",errors=continue");
  } else if (strcmp(fs, "xfs") == 0) {
    strcat(opts, ",nouuid");
  }
  res = mount(source, target, fs, flags, opts);
  if (res == -1) {
    err = errno;
    goto error_clear_loop;
  }
  res = open(target, O_RDONLY | O_DIRECTORY);
  if (res == -1) {
    err = errno;
  }

error_clear_loop:
  if (need_loop_device) {
    ioctl(loopfd, LOOP_CLR_FD, 0);
    close(loopfd);
    close(memfd);
  }
  errno = err;
  return res;
}

int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);

  memcpy((void*)0x20000000, "squashfs\000", 9);
  memcpy((void*)0x20000100, "./file0\000", 8);
  *(uint64_t*)0x20000200 = 0x20010000;
  memcpy(
      (void*)0x20010000,
      "\x68\x73\x71\x73\x07\x00\x00\x00\x91\x1d\x67\x5f\x00\x00\x10\x00\x00\x00"
      "\x00\x00\x04\x00\x14\x00\xd0\x00\x02\x00\x04\x00\x00\x00\x1e\x00\x60\x00"
      "\x00\x00\x00\x00\xf5\x02\x00\x00\x00\x00\x00\x00\x99\x02\x00\x00\x00\x00"
      "\x00\x00\xdd\x02\x00\x00\x00\x00\x00\x00\x06\x01\x00\x00\x00\x00\x00\x00"
      "\xd4\x01\x00\x00\x00\x00\x00\x00\x4d\x02\x00\x00\x00\x00\x00\x00\x87\x02"
      "\x00\x00\x00\x00\x00\x00\xfd\x37\x7a\x58\x5a\x00\x00\x01\x69\x22\xde\x36"
      "\x02\xc0\x17\x64\x21\x01\x10\x00\x0c\x14\xf5\xca\xe0\x00\x63\x00\x0f\x5d"
      "\x00\x39\x9e\x4b\xac\xd2\x52\x69\x94\xd5\x12\xed\xa5\xbf\x00\x00\x00\x00"
      "\x4a\x55\x79\xb2\x00\x01\x27\x64\x0f\xa2\x9c\xb0\x90\x42\x99\x0d\x01\x00"
      "\x00\x00\x00\x01\x59\x5a\xfd\x37\x7a\x58\x5a\x00\x00\x01\x69\x22\xde\x36"
      "\x03\xc0\x1c\x9a\x08\x21\x01\x10\x00\x00\x00\x00\x93\xfc\x58\xde\xe0\x04"
      "\x19\x00\x14\x5d\x00\x39\x9e\x4b\xac\xd2\x52\x69\x94\xd5\x15\x08\xfe\x16"
      "\xca\x84\xa7\xaa\x36\x89\xdf\x00\x98\x88\x96\x66\x00\x01\x30\x9a\x08\x00"
      "\x00\x00\x2e\xc4\x2d\x99\x3e\x30\x0d\x8b\x02\x00\x00\x00\x00\x01\x59\x5a"
      "\x73\x79\x7a\x6b\x61\x6c\x6c\x65\x72\x73\xcc\x00\xfd\x37\x7a\x58\x5a\x00"
      "\x00\x01\x69\x22\xde\x36\x03\xc0\x94\x01\xbe\x02\x21\x01\x02\x00\x00\x00"
      "\x2b\xe6\xa3\x7d\xe0\x01\x3d\x00\x8c\x5d\x00\x01\x00\x1e\xb0\x4f\x26\x2e"
      "\x3c\x2f\x42\x2b\xdb\x8c\x11\x1c\x2e\xea\x0f\xf1\xb7\xf8\x7c\x3c\x98\x93"
      "\x0a\xe9\xbe\xf2\xe6\xcf\xbe\x86\x64\x2d\x31\x26\x30\xd1\xc1\x17\x7c\x3f"
      "\x02\xec\xcf\x24\xfa\x64\x58\x57\x4e\x29\x54\x84\x3d\xbd\x6b\xc9\x86\x80"
      "\x05\x03\x21\x63\x8c\x7a\x93\x37\x5d\xb1\xe7\x1b\xae\x62\x3d\x26\xe9\x09"
      "\x64\x27\xe1\x97\x37\x4c\x50\xe8\x29\xfa\x41\x6b\xd9\x3e\xb4\xfc\xf0\x67"
      "\xeb\x65\x0b\xe2\x18\x78\xe9\xae\x58\xde\x23\x3e\x58\x4b\xfa\x0f\x44\xd8"
      "\x59\x00\xda\xa9\x64\xd5\x3b\x67\xd7\xa1\x21\x5e\x51\x92\x89\x21\xae\xe7"
      "\x27\x93\x82\x66\x11\xb4\x3c\x00\xe5\x99\xfd\x79\x00\x01\xa8\x01\xbe\x02"
      "\x00\x00\x29\x83\x53\xf5\x3e\x30\x0d\x8b\x02\x00\x00\x00\x00\x01\x59\x5a"
      "\x77\x80\x01\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x24\x00\x00\x00"
      "\x02\x00\x04\x00\x66\x69\x6c\x65\x30\x48\x00\x01\x00\x03\x00\x04\x00\x66"
      "\x69\x6c\x65\x31\x04\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00"
      "\x00\x00\x02\x00\x08\x00\x66\x69\x6c\x65\x2e\x63\x6f\x6c\x64\x86\x00\x01"
      "\x00\x01\x00\x04\x00\x66\x69\x6c\x65\x30\xa6\x00\x04\x00\x02\x00\x04\x00"
      "\x66\x69\x6c\x65\x31\xe2\x00\x05\x00\x02\x00\x04\x00\x66\x69\x6c\x65\x32"
      "\xe2\x00\x05\x00\x02\x00\x04\x00\x66\x69\x6c\x65\x33\x38\x80\x00\x00\x00"
      "\x00\x00\x00\x00\x00\x86\x00\x00\x00\x00\x00\x00\x00\x24\x00\x00\x00\x00"
      "\x00\x00\x00\x48\x00\x00\x00\x00\x00\x00\x00\xa6\x00\x00\x00\x00\x00\x00"
      "\x00\xe2\x00\x00\x00\x00\x00\x00\x00\x1e\x01\x00\x00\x00\x00\x00\x00\x4d"
      "\x02\x00\x00\x00\x00\x00\x00\x08\x80\x5c\xf9\x01\x00\x53\x5f\x01\x00\x8f"
      "\x02\x00\x00\x00\x00\x00\x00\x28\x80\x00\x00\x06\x00\x78\x61\x74\x74\x72"
      "\x31\x06\x00\x00\x00\x78\x61\x74\x74\x72\x31\x00\x00\x06\x00\x78\x61\x74"
      "\x74\x72\x32\x06\x00\x00\x00\x78\x61\x74\x74\x72\x32\x10\x80\x00\x00\x00"
      "\x00\x00\x00\x00\x00\x02\x00\x00\x00\x24\x00\x00\x00\xa1\x02\x00\x00\x00"
      "\x00\x00\x00\x01",
      742);
  *(uint64_t*)0x20000208 = 0x2e6;
  *(uint64_t*)0x20000210 = 0;
  *(uint8_t*)0x20010300 = 0;
  syz_mount_image(0x20000000, 0x20000100, 0x1000, 1, 0x20000200, 0, 0x20010300);
  return 0;
}